The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Air pressure determines the air quality in a building. In HVAC systems, the static air pressure is often referred to as the system blood pressure. If the static pressure is not managed properly the systems cannot function properly. Excessive static drop in heating and cooling systems kills the system efficiency, reduces airflow greatly, causes discomfort, causes excessive noise, causes air quality issues, damages equipment, and shortens the lifespan.
Getting accurate air pressure readings enables technicians the ability to correct all of these issues. As such, in the HVAC industry, there are several techniques that are used to determine the air velocity. In this field, air velocity (distance traveled per unit of time) is usually expressed in linear feet per minute (LFM) or meters per second (m/s). By multiplying air velocity by the cross section area of an air duct, you can determine the air volume flowing past a point in the duct per unit of time. Volume flow is measured in cubic feet per minute (CFM) or cubic meters per hour (M3/h).
Velocity or volume measurements can often be used with engineering handbooks or design information to reveal proper or improper performance of an airflow system. The same principles used to determine velocity are also valuable in working with pneumatic conveyance. To move air, fans or blowers are usually used. They work by imparting motion and pressure to the air with either a screw propeller, impeller, cage, or paddle wheel action. When force or pressure from the fan blades causes the air to move, the moving air acquires a force or pressure component in its direction of motion due to its weight and inertia. Because of this, a flag or streamer will stand out in the air stream. This force is called velocity pressure.
Velocity pressure is typically measured in inches of water column (w.c.) or water gauge (w.g.). In HVAC duct systems, a second pressure is always present. It is independent of air velocity or movement. Known as static pressure, it applies pressure equally in all directions. In air conditioning work, this pressure is also measured in inches of water column. In pressure or supply systems, static pressure will be positive on the discharge side of the fan. In exhaust systems, a negative static pressure will exit on the inlet side of the fan. When a fan is installed midway between the inlet and discharge of a duct system, it is normal to have a negative static pressure at the fan inlet and positive static pressure at its discharge.
Total pressure is the combination of static and velocity pressures, and is utilized to determine the health of an HVAC system and/or to make adjustments to the same in order to increase efficiency.
There are many known commercially available manometer devices which can function to assist HVAC technicians and/or engineers to gather and calculate various elements of the total pressure within HVAC systems. To this end, each of these devices are specialty-built standalone equipment having dedicated components such as a dedicated processor and memory, display screen, user keyboard and sensors. As such, these devices are expensive to manufacture and are typically limited to performing certain types of building measurements.
In addition to the above, it is sometimes necessary to factor environmental conditions such as atmospheric pressure, humidity levels and/or barometric pressures into the pressure readings obtained within an HVAC system, in order to obtain a true and accurate system reading. At the present time, any adjustments based on environmental conditions must be performed manually owing to the limited capacity of existing systems.
Accordingly, it would be beneficial to provide an air pressure device and system which can utilize the processing and communicative abilities of a smartphone to obtain and distribute accurate pressure readings that does not suffer from the drawbacks of the above noted devices.